DE112012005487B4 - Wheel position detection device and tire pressure detection device with the same - Google Patents

Abstract

A wheel position detecting device for a vehicle having a vehicle body (6) and a plurality of wheels (5a to 5d), the wheel position detecting device comprising:
a transmitter (2) which is integrated on each of the plurality of wheels (5a to 5d), the transmitter (2) having a first control unit (23), the first control unit (23) having a frame which contains identification information which is specific for the transmitter (2); and
a receiver (3) which is integrated on the vehicle body (6), the receiver (3) having an antenna (31) and a second control unit (33), the second control unit (33) the frame which is transmitted by the transmitter (2) is transmitted via the antenna (31), the second control unit (33) performing a wheel position detection to determine on which of the plurality of wheels (5a to 5d) the transmitter (2) which is transmitting the frame , is integrated, and to store a relationship between the identification information of the transmitter (2) and a corresponding wheel (5a to 5d) on which the transmitter (2) is integrated, wherein
the transmitter (2) has an acceleration sensor (22) which outputs a detection signal according to an acceleration which has a gravitational acceleration component which varies with the rotation of the corresponding wheel (5a to 5d) on which the transmitter (2) is integrated,
wherein the first control unit (23) detects an angular position of the transmitter (2) relative to a reference position based on the gravitational acceleration component provided by the detection signal of the acceleration sensor (22), the reference position to any Position in a circumferential direction of the corresponding wheel (5a to 5d) is set,
wherein the first control unit (23) transmits the frame when the transmitter (2) is at a transmission angular position, and
wherein the first control unit (23) changes the transmission angular position by a predetermined angle each time the frame is transmitted,
wherein the wheel position detecting device further comprises:
a wheel speed sensor (11a to 11d) arranged to correspond to each of the wheels (5a to 5d) around a tooth of a gear (12a to 12d) which rotates in association with the corresponding wheel (5a to 5d) , the gear (12a to 12d) having conductive portions as teeth and intermediate portions between the conductive portions, the intermediate portions having a magnetic resistance different from the conductive portions, wherein
the second control unit (33) acquires gear information indicating a tooth position of the gear (12a to 12d) based on a detection signal of the wheel speed sensor (11a to 11d), and
the second control unit (33) determines on which of the plurality of wheels (5a to 5d) the transmitter is integrated, based on the tooth position of the gearwheel at a reception timing of the frame, wherein
the second control unit (33) sets a deviation allowance range of the tooth position based on the tooth position of the gear (12a to 12d) at the reception timing of the frame,
the second control unit (33) determines whether the tooth position of the gearwheel (12a to 12d) is within the deviation permissible range at a subsequent reception timing of the frame,
if the tooth position of the gear (12a to 12d) at the subsequent reception timing is not within the deviation allowance range, the second control unit (33) selects the gear (5a to 5d) corresponding to the gear (12a to 12d) of candidate gears (5a to 5d) ) until one wheel (5a to 5d) remains and one wheel (5a to 5d) registers as the wheel (5a to 5d) on which the transmitter (2) is integrated,
the second control unit (33) changes the deviation allowance range every time the frame is received,
the second control unit (33) sets an overlapping area between the deviation allowance range and a preceding deviation allowance range, which was set based on the tooth position of the gear (12a to 12d) at a previous reception timing of the frame, as a new deviation allowance range,
the second control unit (33) the tooth position of the gear (12a to 12d), which is detected at the reception timing assigned to the frame which is transmitted at a transmission angle position which is changed by the first control unit (23), to a Corrected tooth position which is assigned to a frame which is transmitted to a fixed transmission angle position, and
the second control unit (33) determines whether the tooth position of the gear (12a to 12d) which is corrected is within the deviation allowance range in order to determine the gear (5a to 5d) on which the transmitter (2) is integrated.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is based on Japanese Patent Application No. 2011-286186 , filed September 27, 2011, the disclosure of which is incorporated herein by reference.

TECHNICAL AREA

The present disclosure relates to a wheel position detection device and a tire pressure detection device that the wheel position detection device has.

STATE OF THE ART

In general, a wheel position detecting device detects a position of a subject wheel in a vehicle. It is also known to use a wheel position detection device in a tire pressure detection device for detecting a tire pressure of a wheel. As an example of the tire pressure detecting device, a direct type tire pressure detecting device is known.

In the direct type tire pressure detecting device, a transmitter is attached directly to a wheel with a tire. The transmitter is provided with a sensor such as a pressure sensor. A vehicle body is equipped with an antenna and a receiver. When the transmitter transmits a detection signal of the sensor, the receiver receives the detection signal through the antenna and detects the tire pressure of the wheel based on the detection signal.

In such a direct type tire pressure detecting device, data transmitted from the transmitter includes ID information for identifying whether the transmitted data relates to a subject vehicle equipped with the tire pressure detecting device and for identifying the wheel to which the transmitter that transmits the data is attached.

In order to specify the position of the transmitter based on the ID information of the transmitted data, the receiver stores in advance a relationship between the ID information of each transmitter and the position of each wheel. When the positions of the wheels are changed by one rotation of the tire, it is necessary to re-register the relationship between the ID information of each transmitter and the position of each wheel. For example, Patent Literature 1 describes a tire pressure monitoring device and a tire pressure monitoring method for automatically registering the relationship between the ID information of each transmitter and the position of each wheel.

The tire pressure monitoring device of Patent Literature 1 detects that a wheel is at a predetermined rotating position based on an acceleration detection signal from an acceleration sensor provided in the transmitter and detects a rotating position of a wheel when the receiver receives a radio signal from a transmitter. The tire pressure monitor specifies the position of the wheel by monitoring a change in a relative angle between the rotational position detected by the transmitter and the rotational position of the wheel when the receiver receives the radio signal from the transmitter.

That is, the change in the relative angle between the rotational position of the wheel detected by a wheel-side unit attached to the wheel and the rotational position of the wheel detected by a body-side unit attached to the vehicle body monitored based on a deviation of a predetermined number of data.

The position of the wheel is specified by determining whether a variation in the change in relative angle relative to an initial value is above an acceptable value.

In the method described in Patent Literature 1, the radio signal is transmitted when the wheel is at the predetermined rotating position. However, there is a position where the radio signal is likely to be difficult to reach the body side unit, and such a position is the so-called zero. Accordingly, when the radio signal is transmitted when the rotational position of the wheel is at the zero point, the radio signal is less likely to reach the body side unit even if the radio signal is transmitted many times. In such a case, it takes time to detect the position of the wheel or it is difficult to detect the position of the wheel.

Patent Literature 1: Japanese Patent Application Publication No. 2010-122023.

Further prior art can be found in the following documents.

DE 10 2008 049 046 A1 discloses a method, a sensor, a detector and a System for the localization of at least one wheel on a vehicle. A signal from a first sensor mounted on the wheel, which signal indicates a position of the wheel, is received. In addition, a measured value from a second sensor, which measures the angular position of a wheel and is assigned to a specific point on the vehicle, is received. If the phase position of the first signal in relation to the measured value remains within a predetermined tolerance range in a specific observation period, the first sensor can be assigned to the second sensor.

DE 10 2009 059 788 A1 discloses a method and a device for localizing the installation positions of vehicle wheels in a motor vehicle, in which at least one vehicle wheel has wheel electronics, with the steps of: determining, on the wheel electronics side, a first angular position of the vehicle wheel assigned to this wheel electronics; Sending a transmission signal with a first angle of rotation information dependent on the determined first angle of rotation position; Determination of second rotational angle positions of the vehicle wheels on the vehicle side and, as a function thereof, providing second rotational angle information; Matching the first rotation angle information with the second rotation angle information; Determining the installation position of the vehicle wheel assigned to the wheel electronics as a function of this comparison.

US 2011/0 071 737 A1 discloses systems and methods for the automatic positioning of tire pressure monitoring sensor units on a vehicle, the systems and methods measuring the angle of a wheel at two different points in time using a sensor mounted on the rim or on the tire and determining a difference between the measured angles. The systems and methods provide for the angle and / or the difference in the measured angles to be transmitted to an electronic control module together with a sensor identification. Alternatively, the systems and methods provide for the transmission of time differences to the electronic control module. The electronic control module correlates the information transmitted by the wheel unit with the data from the anti-lock braking system. A location of the wheel to which the sensor is attached is determined and the sensor identification is assigned.

JP 2006 138 803 A discloses an apparatus for obtaining a wheel condition. A TPMS unit to be mounted on a wheel includes both a wheel-mounted communication device and a G-sensor. The detection results of the G sensor are communicated to the ECU through the wheel-mounted communication device and a communication device mounted on the vehicle body. Pulse signals sent from a magnetic rotor that rotates in synchronism with the rotation of the wheel are transmitted to the ECU through a magnetic pickup. The ECU derives the rotational position of the TPMS unit during the rotation of the wheel from the correspondence between the acceleration recorded by the G sensor in the effective direction of a centrifugal force and the pulse signals recorded by the magnetic pick-up.

JP 2010 - 122 023 A discloses an apparatus and method for tire pressure monitoring. The rotational position of each of the wheels is detected on a wheel side and a body side, the rotational position detected on the wheel side being transmitted together with a sensor ID to a receiver using a radio signal, the variation of each relative angle between the rotational position received from the transmitter and the rotational position of each wheel detected on the body side when the former rotational position is received is monitored, the wheel position obtained by detecting the rotational position whose relative angular variation is the smallest after traveling a predetermined distance as the wheel position of the transmitter is determined, and wherein the sensor ID received from the transmitter, the wheel position of which is determined, is registered as the sensor ID of the tire of the wheel position by a memory update in the memory.

DE 10 2009 059 789 A1 discloses wheel electronics for a vehicle wheel and a vehicle. The wheel electronics have a sensor that is designed to receive a measurement signal that has at least one first wheel-specific parameter, and an evaluation device that is designed to determine a current rotational position of the vehicle wheel at the time of the measurement from the measurement signal.

DE 198 49 390 A1 discloses a method for performing the assignment of air pressure control devices to wheel positions in an air pressure control system of a motor vehicle. To carry out the method, the signals from the speed sensors of a slip control system must be evaluated in a first central unit of the air pressure control system. The speed sensors first transmit the signal they generate to a second central unit of the slip control system and from there they are transmitted via a data bus to the first central unit in order to be evaluated there. This data transmission path ensures that the air pressure control system does not restrict the functionality and safety of the slip control system.

SHORT VERSION

It is an object of the present disclosure to provide a wheel position detecting device capable of specifying a wheel position accurately and easily, and to provide a tire pressure detecting device having the wheel position detecting device.

According to a first aspect of the present disclosure, a wheel position detecting device includes a transmitter, a receiver, and a wheel speed sensor. The transmitter is integrated on each of the wheels of a vehicle. The transmitter has a first control unit which generates and transmits a frame which has identification information or identification information which is specific for the transmitter. The receiver is integrated on a vehicle body. The receiver has an antenna and a second control unit. The second control unit receives the frame transmitted by the transmitter via the antenna. The second control unit performs wheel position detection to specify on which of the plurality of wheels the transmitter which transmits the frame is integrated and to establish a relationship between the identification information of the transmitter and a corresponding wheel in which the transmitter is integrated, save.

The transmitter furthermore has an acceleration sensor which outputs a detection signal according to an acceleration which has a gravitational acceleration component which varies with the rotation of the corresponding wheel on which the transmitter is integrated. The first control unit detects an angular position of the transmitter relative to a reference position based on the gravitational acceleration component which is provided by the detection signal of the acceleration sensor. The reference position is selected or set at any position in a circumferential direction of the corresponding wheel.

The first control unit transmits the frame when the transmitter is at a transmission angular position. The first control unit changes the transmission angular position by a predetermined angle each time the frame is transmitted. The wheel speed sensor is arranged to correspond to each of the wheels to detect a tooth of a gear which rotates in association with the corresponding wheel. The gear has conductive portions such as teeth and intermediate portions between the conductive portions. The intermediate sections have a magnetic resistance different from the conductive sections. The second control unit acquires gear information indicating a tooth position of the gear based on a detection signal from the wheel speed sensor. The second control unit specifies on which of the plurality of gears the transmitter is integrated, based on the tooth position of the gear at a reception timing of the frame.

In the above wheel position detecting device, the transmission angular position of the transmitter is changed by the predetermined angle every time the transmitter transmits the frame. Accordingly, the frame is properly received by the recipient. The wheel position detection is carried out precisely and without problems.

According to a second aspect of the present disclosure, the second control unit sets a deviation allowance range of the tooth position based on the tooth position of the gear at the reception timing of the frame. The second control unit determines whether the tooth position of the gearwheel is within the deviation permissible range during a subsequent reception time specification of the frame. If the tooth position of the gear at the subsequent reception timing is not within the deviation allowance range, the second control unit excludes the wheel corresponding to the gear from candidate wheels until one wheel remains, and registers the one wheel as the wheel on which the transmitter is integrated is.

Furthermore, the second control unit changes the deviation allowance range every time the frame is received. The second control unit sets an overlapping area between the deviation allowance range and a previous deviation allowance range, which was set based on the tooth position of the gear at a previous reception timing of the frame, as a new deviation allowance range. The second control unit corrects the tooth position of the gear detected at the reception timing associated with the frame transmitted at a transmission angular position changed by the first control unit to a tooth position associated with a frame , which is transmitted at a fixed transmission angular position. The second control unit determines whether the tooth position of the gear which is corrected is within the deviation allowance range in order to specify the gear on which the transmitter is integrated.

According to a third aspect of the present disclosure, instead of correcting the detected tooth position, the second one calculates Control unit an overlapping area between the deviation allowance range and a first added deviation allowance range, which is provided by adding a predetermined deviation allowance range to a previous deviation allowance range, which is set at a previous reception timing of the frame. The second control unit sets a second added deviation allowance range, which is determined by adding the predetermined deviation allowance range to the overlapping range that has been calculated, as a new deviation allowance range.

The wheel position detecting device according to the first to third aspects described above can be applied to a tire pressure detecting device. In such a case, the transmitter has a detection unit which outputs a detection signal in accordance with a tire pressure of the corresponding wheel. The first control unit generates tire pressure information or tire pressure information which indicates the detection signal of the detection unit. The first control unit adds the tire pressure information to the frame and transmits the frame. The second control unit detects the tire pressure of each wheel based on the tire pressure information contained in the frame.

Figure list

• 1 ist ein schematisches Diagramm zum Veranschaulichen einer Gesamtstruktur einer Radpositions-Erfassungsvorrichtung und einer Gesamtstruktur einer Reifendruck-Erfassungsvorrichtung, welche die Radpositions-Erfassungsvorrichtung gemäß einer Ausführungsform der vorliegenden Offenbarung einsetzt;
• 2A ist ein schematisches Blockschaltbild eines Transmitters der Radpositions-Erfassungsvorrichtung gemäß der Ausführungsform;
• 2B ist ein schematisches Blockschaltbild eines Empfängers der Reifenpositions-Erfassungsvorrichtung gemäß der Ausführungsform;
• 3 ist ein Zeitdiagramm zum Erklären einer Radpositions-Erfassung, welche durch die Radpositions-Erfassung gemäß der Ausführungsform durchgeführt wird;
• 4 ist ein schematisches Diagramm zum Veranschaulichen einer Änderung von Zahnradinformationen gemäß der Ausführungsform;
• 5A ist ein schematisches Diagramm zum Erklärung eines Abweichungszulässigkeitsbereichs, welcher in einer Radpositions-Spezifizierlogik gemäß der Ausführungsform verwendet wird;
• 5B ist ein schematisches Diagramm zum Erklärung eines Abweichungszulässigkeitsbereichs, welcher in der Radpositions-Spezifizierlogik gemäß der Ausführungsform verwendet wird;
• 5C ist ein schematisches Diagramm zum Erklärung eines Abweichungszulässigkeitsbereichs, welcher in der Radpositions-Spezifizierlogik gemäß der Ausführungsform verwendet wird;
• 6A ist ein Diagramm, welches ein Auswerteergebnis der Radpositions-Spezifizierlogik hinsichtlich eines Frames, welcher die erste Identifikationsinformation gemäß der Ausführungsform aufweist, spezifiziert;
• 6B ist ein Diagramm, welches ein Auswerteergebnis der Radpositions-Spezifizierlogik hinsichtlich eines Frames, welcher die zweite Identifikationsinformation gemäß der Ausführungsform aufweist, spezifiziert;
• 6C ist ein Diagramm, welches ein Auswerteergebnis der Radpositions-Spezifizierlogik hinsichtlich eines Frames, welcher die dritte Identifikationsinformation gemäß der Ausführungsform aufweist, spezifiziert;
• 6D ist ein Diagramm, welches ein Auswerteergebnis der Radpositions-Spezifizierlogik hinsichtlich eines Frames, welcher die vierte Identifikationsinformation gemäß der Ausführungsform aufweist, spezifiziert;
• 7A ist ein schematisches Diagramm eines Rades zum Erklären einer Übertragungs-Winkelposition des Transmitters gemäß der Ausführungsform;
• 7B ist ein schematisches Diagramm, welches eine Beziehung zwischen einer Zeit veranschaulicht, zu der der Frame übertragen wird und der Übertragungs-Winkelposition des Transmitters gemäß der Ausführungsform;
• 8A ist ein schematisches Diagramm eines Beispiels eines Frames, welcher von dem Transmitter gemäß der Ausführungsform übertragen wird;
• 8B ist ein schematisches Diagramm eines anderen Beispiels eines Frames, welcher von dem Transmitter gemäß der Ausführungsform übertragen wird, und
• 9 ist ein Diagramm, welches ein Auswerteergebnis einer Radpositions-Spezifizierlogik eines Falles veranschaulicht, in dem der Winkel des Transmitters jedes Mal geändert wird, wenn der Transmitter den Frame gemäß der Ausführungsform überträgt.

The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description made with reference to the accompanying drawings. In the drawings:

• 1 13 is a schematic diagram illustrating an overall structure of a wheel position detecting device and an overall structure of a tire pressure detecting device employing the wheel position detecting device according to an embodiment of the present disclosure;
• 2A Fig. 13 is a schematic block diagram of a transmitter of the wheel position detecting device according to the embodiment;
• 2 B Fig. 13 is a schematic block diagram of a receiver of the tire position detecting device according to the embodiment;
• 3 Fig. 13 is a time chart for explaining wheel position detection performed by the wheel position detection according to the embodiment;
• 4th Fig. 13 is a schematic diagram for illustrating change of gear information according to the embodiment;
• 5A Fig. 13 is a schematic diagram for explaining a departure allowance range used in a wheel position specifying logic according to the embodiment;
• 5B Fig. 13 is a schematic diagram for explaining a departure allowance range used in the wheel position specifying logic according to the embodiment;
• 5C Fig. 13 is a schematic diagram for explaining a departure allowance range used in the wheel position specifying logic according to the embodiment;
• 6A Fig. 13 is a diagram specifying an evaluation result of the wheel position specifying logic with respect to a frame including the first identification information according to the embodiment;
• 6B Fig. 13 is a diagram specifying an evaluation result of the wheel position specifying logic with respect to a frame including the second identification information according to the embodiment;
• 6C Fig. 13 is a diagram specifying an evaluation result of the wheel position specifying logic with respect to a frame including the third identification information according to the embodiment;
• 6D Fig. 13 is a diagram specifying an evaluation result of the wheel position specifying logic with respect to a frame including the fourth identification information according to the embodiment;
• 7A Fig. 13 is a schematic diagram of a wheel for explaining a transmission angular position of the transmitter according to the embodiment;
• 7B Fig. 13 is a schematic diagram illustrating a relationship between a time at which the frame is transmitted and the transmission angular position of the transmitter according to the embodiment;
• 8A Fig. 13 is a schematic diagram of an example of a frame transmitted from the transmitter according to the embodiment;
• 8B FIG. 13 is a schematic diagram of another example of a frame transmitted from the transmitter according to the embodiment, and FIG
• 9 Fig. 13 is a diagram illustrating an evaluation result of a wheel position specifying logic of a case where the angle of the transmitter is changed every time the transmitter transmits the frame according to the embodiment.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The same parts are denoted by the same reference symbols throughout the embodiments.

An embodiment is described with reference to FIG 1 until 9 to be discribed.

1 Fig. 13 is a schematic diagram showing an overall structure of a wheel position detection device and an overall structure of a tire pressure detection device in a vehicle 1 illustrated. In 1 an upward direction corresponds to a front direction of the vehicle 1 and a downward direction corresponds to a rearward direction of the vehicle 1 . The tire pressure sensing device according to the present embodiment will be described with reference to FIG 1 to be discribed.

The tire pressure sensing device is on the vehicle 1 set up. The tire pressure detection device has a transmitter 2 , a tire pressure monitoring system electronic control unit (hereinafter referred to as the TPMS-ECU) 3 and a measuring device 4th on. The TPMS-ECU 3 serves as a receiver.

The wheel position detecting device uses the transmitter 2 and the TPMS-ECU 3 the tire pressure detecting device. The wheel position detecting device specifies a position of a wheel 5 ( 5a until 5d ) by obtaining gear information of a brake electronic control unit (hereinafter referred to as the brake ECU) 10 . The gear information is based on a detection signal from a wheel speed sensor 11a until 11d provided, which is arranged so that it fits each of the wheels 5a until 5d is equivalent to.

The transmitter 2 is in each of the wheels 5a until 5d integrated. The transmitter 2 detects a tire pressure such as a tire air pressure as information relating to a tire pressure in a frame and transmits the frame.

The TPMS-ECU 3 is on a body 6th of the vehicle 1 integrated. The TPMS-ECU 3 receives the frame sent by the transmitter 2 is transmitted. The TPMS-ECU also performs 3 a wheel position detection and a tire pressure detection by performing various processes and calculations based on data stored in the frame.

For example, the transmitter generates 2 the frame by frequency modulation (Frequency Shift Keying, FSK). The TPMS-ECU 3 demodulates the frame to read data in the frame and detects the wheel position and tire pressure based on the read data. 2A is a schematic block diagram of the transmitter 2 , and 2 B Fig. 13 is a schematic block diagram of the TPMS-ECU 3 .

As in 2A shown indicates the transmitter 2 a recognition unit 21 , an accelerometer 22nd , a microcomputer 23 , a transmission circuit 24 and a transmission antenna 25th on. The recognition unit 21 , the accelerometer 22nd , the microcomputer 23 , the transmission circuit 24 and the transmission antenna 25th are operated by electrical power, which is provided by a battery (not shown).

The recognition unit 21 has a pressure sensor 21a and a temperature sensor 21b on. The pressure sensor 21a is, for example, a diaphragm type pressure sensor. The scanning unit 21 outputs a detection signal according to the tire pressure and a detection signal according to a temperature.

The accelerometer 22nd is used to record its position within the corresponding wheel 5a until 5d on which the transmitter 2 is integrated. That is called the accelerometer 22nd is used to acquire a position of the transmitter 2 used. The acceleration sensor is also used to detect a speed of the vehicle 1 used. The accelerometer 22nd gives a detection signal according to the accelerations in both radial directions of the corresponding wheel 5a until 5d off, that is, accelerations in both directions at right angles to a circumferential direction of the corresponding wheel 5a until 5d .

The microcomputer 23 can be a well known type of microcomputer. The microcomputer 23 includes a control unit (first control unit) and the like. The microcomputer 23 performs a predetermined process in accordance with a program stored in a memory of the control unit. The memory of the storage unit has individual ID Information including the transmitter identification information and the vehicle identification information. The transmitter identification information is specific to the transmitter in question 2 to identify the affected transmitter 2 . The vehicle identification information is specific to the vehicle in question 1 to the vehicle in question 1 to identify.

The microcomputer 23 receives the detection signal indicative of the tire pressure from the recognition unit 21 and processes the detection signal to generate the tire pressure information. The microcomputer also stores 23 the information regarding the tire pressure as well as the ID information of the transmitter 2 in the frame.

The microcomputer also monitors 23 the detection signal from the acceleration sensor 22nd . The microcomputer 23 detects the position of the relevant transmitter within the corresponding wheel 5a until 5d and detects the speed of the vehicle 1 based on the detection signal from the acceleration sensor 22nd .

When the microcomputer 23 generates the frame, the microcomputer transmits 23 the frame (data) in the direction of the TPMS-ECU 3 via the transmission circuit 24 and the transmission antenna 25th based on detection results of the position of the subject transmitter 2 and the speed of the vehicle 1 .

In particular, the microcomputer starts 23 transmit the frame when the vehicle is moving 1 moved. The microcomputer also transmits 23 the frame every time the accelerometer 22nd is at a predetermined angular position relative to a reference position based on the detection signal of the acceleration sensor 22nd . The microcomputer 23 determines whether the vehicle 1 moves based on the detection result of the acceleration sensor 22nd . The microcomputer also determines 23 the angular position of the accelerometer 22nd based on the detection result of the position of the transmitter 2 which is based on the detection signal of the acceleration sensor 22nd is obtained.

The microcomputer 23 namely, detects the vehicle speed using the detection signal of the acceleration sensor 22nd and determines that the vehicle 1 moves when the vehicle speed is equal to or greater than a predetermined speed such as 5 km / h or more. The output of the accelerometer 22nd contains acceleration (centrifugal acceleration) based on centrifugal force.

The vehicle speed is calculated by integrating the centrifugal accelerations and multiplying a coefficient. The microcomputer calculates accordingly 23 the centrifugal acceleration by removing a gravitational acceleration component from the output of the acceleration sensor 22nd , and it calculates the vehicle speed based on the calculated centrifugal acceleration.

The accelerometer 22nd gives the detection signal according to the rotation of the corresponding wheel 5a until 5d the end. Accordingly, if the vehicle contains 1 moves, the detection signal of the acceleration sensor 22nd the gravitational acceleration. As such, the detection signal has an amplitude corresponding to the rotation of the corresponding wheel 5a until 5d .

For example, the amplitude of the detection signal has a maximum negative value when the transmitter 2 exactly above a central axis of the corresponding wheel 5a until 5d (Wheel center axis) and it has a maximum positive value when the transmitter is placed just below the wheel center axis. Furthermore, the amplitude of the detection signal has a value of zero when the transmitter 2 is at the same level as the wheel center axis.

Accordingly, the angular position of the acceleration sensor 22nd based on the amplitude. For example, a position exactly above the wheel center axis is defined as a reference position, such as a 0-degree position. The angular position of the accelerometer 22nd is defined relative to the reference position. The reference position can be any position on a circumferential direction of the wheel 5a until 5d be.

The transmitter 2 starts transmitting the frame when the vehicle speed reaches a predetermined speed, or when the acceleration sensor 22nd is at the predetermined angular position after the vehicle speed reaches the predetermined speed. The transmitter can also 2 the frame is transmitted every time the accelerometer 22nd the angular position becomes the same as the angular position when the frame is transmitted for the first time, as a transmission timing. The transmitter 2 namely, transmits the frame repeatedly.

In terms of transmission timing, the frame can be transmitted every time the acceleration sensor 22nd reaches the angular position the same as the angular position when the frame is transmitted for the first time. However, it may not always be necessary to transmit the frame every time the accelerometer is 22nd reached the same angular position. Taking into account a battery life or a battery life, the transmitter can 2 transmit the frame at a predetermined interval or a predetermined period of time, for example every 15 seconds.

The transmission circuit 24 serves as an output unit which the frame sent from the microcomputer 23 is provided, receives and the frame in the direction of the TPMS-ECU 3 via the transmission antenna 25th transmits. For example, the frame is transmitted over an RF radio band wave.

The transmitter 2 is, for example, on an air inlet valve of the corresponding wheel 5a until 5d attached such that the recognition unit 120 exposed inside the tire. The pressure sensor 21a of the transmitter 2 records the tire pressure. As described above, when the vehicle speed exceeds the predetermined speed, the transmitter transmits 2 the frame via the transmission antenna 25th every time the acceleration sensor is at the predetermined angular position.

After that, it may be possible to transmit the frame continuously every time the accelerometer is used 22nd is at the predetermined angular position. However, in consideration of the battery life, it is preferable to increase a transmission interval. Thus, when a predetermined period of time necessary for specifying the wheel position has passed, the transmitter can 2 can be switched from a wheel position specifying mode to a regular transmission mode.

The transmitter transmits in the regular transmission mode 2 regularly the frame in the direction of the TPMS-ECU 3 at a constant interval such as every one minute which is longer than the transmission interval in the wheel position specifying mode. In this case it may be possible, for example, to set the transmission time of the frame between the transmitters 2 by inserting an arbitrary delay for each transmitter 2 to differentiate or differentiate. In such a case, the interference of radio waves from the plurality of transmitters becomes 2 will be decreased and the frames will be properly handled by the TPMS-ECU 3 receive.

As in 2 B shown is the TPMS-ECU 3 a receiving antenna 31 , a receiving circuit 32 and a microcomputer 33 on. The TPMS-ECU 3 acquires the gear information from the brake ECU 10 via a local area network (LAN) located in the vehicle, such as a controller area network (CAN).

In the vehicle 1 are gears 12a until 12d arranged to be each in connection with the wheels 5a until 5d to turn. The TPMS-ECU 3 receives a tooth position of each gear 12a until 12d which is represented by a margin number or a tooth number based on the gear information.

The receiving antenna 31 is intended to be the frame sent by each transmitter 2 is transmitted, received. The receiving antenna 31 is on the vehicle body 6th attached. The receiving antenna 31 can be an internal antenna which is inside the body of the TPMS-ECU 3 is arranged. Alternatively, the receiving antenna 31 an external antenna which is outside the body of the TPMS-ECU 3 is arranged and with the body of the TPMS-ECU 3 connected by a wire.

The receiving circuit 32 serves as an input section containing the frame sent from each transmitter 2 is transmitted via the receiving antenna 31 and receives the frame to the microcomputer 33 sends. When the receiving circuit 32 namely, one signal (one frame) through the receiving antenna 31 receives, the receiving circuit transmits 32 the received signal to the microcomputer 33 .

The microcomputer 33 corresponds to a second control unit. The microcomputer 33 performs a wheel position detection process in accordance with a program stored in a memory of the microcomputer 33 is saved by. In particular, the microcomputer performs 33 the wheel position detection based on a relationship between information received from the brake ECU 10 can be obtained, and a reception time, which is the frame transmitted by the transmitter 2 is transmitted receives, through. The microcomputer 33 acquires the gear information from the brake ECU 10 at a predetermined time interval such as every 10 milliseconds.

The gear information shows the tooth position of the gear 12a until 12d , which can be found in connection with the corresponding wheel 5a until 5d turns on. The tooth position of the gear 12a until 12d is detected using a wheel speed sensor 11a until 11d which is arranged around the gear 12a until 12d correspond to.

For example, is the wheel speed sensor 11a until 11d provided by an electromagnetic pickup sensor which is arranged to have teeth of the corresponding gear 12a until 12d opposite. A Detection signal received from the wheel speed sensor 11a until 11d is output changes according to the teeth of the gear 12a until 12d , which by the wheel speed sensor 11 a through 11d. The wheel speed sensor 11 a to 11d output a rectangular pulse wave corresponding to the teeth as the detection signal. Edges of the teeth of the gear 12a until 12d are indicated by rising edges and falling edges of the right-angled pulse wave.

The brake ECU 10 detects the number of edges, that is, it counts the number of edges detected by the wheel speed sensor 11a until 11d are passed based on the number of rising edges and falling edges of the detection signal. The brake ECU 10 sees a current edge number for the microcomputer 33 at a predetermined interval as the gear information. As a result, the microcomputer 33 determine which tooth of the gear 12a until 12d by the wheel speed sensor 11a until 1 1d passed through at a time.

The number of edges is reset every time the gear 12a until 12d rotates one revolution. For example, in one case of a gear, which 48 Teeth has the number of margins 96 . In this case, the number of edges is counted from 0 to 95. When the number of edges that is counted reaches 95, the number of edges returns to 0 and is counted from 0 again.

In the example described above, the edge number is from the brake ECU 10 for the microcomputer 33 provided as the gear information. As another example, a number of teeth, that is, the number of teeth that is counted, can be provided by the brake ECU 10 for the microcomputer 33 may be provided as the gear information. As another further example, the number of edges or the number of teeth detected by the wheel speed sensor 11a until 11d has passed in a predetermined period of time for the microcomputer 33 be provided, and the microcomputer 33 may add the number of edges or the number of teeth provided to a preceding edge number or number of teeth to detect the number of edges or the number of teeth. That is, a way of detecting the number of edges or the number of teeth cannot be limited to a specific way as long as the microcomputer 33 finally obtains the number of edges or the number of teeth as the gear information.

The brake ECU 10 resets the number of edges or the number of teeth when the power supply is switched off. The brake ECU 10 starts counting the number of edges or the number of teeth again when the power supply is turned on or when the vehicle speed reaches the predetermined speed after the power supply is turned on. In this way, even if the number of edges or the number of teeth is reset every time the power is turned off, the same tooth with the same number of edges or the same number of teeth is displayed while the electric power is turned off.

When the microcomputer 33 the frame receives which from each transmitter 2 is transmitted, the microcomputer measures 33 the reception timing of receiving the frame, and performs the wheel position detection based on the edge number or the number of teeth at the reception timing of the frame among the edge numbers or the number of teeth obtained. Thus, the wheel position detection can be used to specify which of the wheels 5a until 5d the respective transmitter 2 is integrated. The wheel position detection will be described in more detail later.

The microcomputer 33 stores a relationship between the ID information of each transmitter 2 and the position of each wheel 5a until 5d on which the transmitter 2 is integrated, based on the result of the wheel position detection. The microcomputer then detects 33 the tire pressure of each wheel 5a until 5d based on the ID information and the tire pressure information stored in the frame sent from each transmitter 2 is transmitted. The microcomputer also gives 33 an electrical signal according to the tire pressure to the measuring device 4th via the LAN in the vehicle, such as the CAN.

For example, the microcomputer detects 33 a decrease in the pressure of the tire by comparing the sensed tire pressure to a predetermined limit value. When the microcomputer 33 The microcomputer reports the decrease in tire pressure 33 a signal indicating the decrease in the tire pressure of the measuring device 4th indicates. The microcomputer 33 namely the measuring device 4th about the position of the wheel 5a until 5d whose tire pressure is reduced.

The measuring device 4th serves as a warning section. As in 1 shown is the measuring device 4th arranged at a position which can be seen by a vehicle operator. For example, the measuring device 4th a meter display and the like disposed within an instrument panel of the vehicle 1 . For example, if the measuring device 4th the signal indicating the decrease in tire pressure from which Microcomputers 33 the TPMS-ECU 3 receives, the measuring device shows the decrease in tire pressure with the display of the wheel 5a until 5d at. The measuring device 4th namely notifies the vehicle driver of the decrease in the tire pressure of a certain wheel 5a until 5d .

Next, an operation of the tire pressure detecting device will be described. In the following description, the wheel position detection and the tire pressure detection performed by the tire pressure detection device will be explained separately.

First, the wheel position detection will be described.

As a reference, first, an operation of the wheel position detection without considering the zero position will be described. 3 Fig. 13 is a timing chart for explaining wheel position detection. 4th Fig. 13 is a diagram illustrating a map of a change in gear information after an ignition switch is turned on and the vehicle 1 begins to move. For example illustrates 4th the gear information when the ignition switch is turned on and at first to third times after the vehicle 1 begins to move. the 5A until 5C are schematic diagrams for explaining wheel position specifying logic. the 6A until 6D are diagrams illustrating evaluation results in the wheel position specifying logic. The procedure for specifying the positions of the wheels 5a until 5d will be described in detail with reference to the 3 until 6D to be discribed.

In the transmitter 2 becomes the microcomputer 23 supplied with electrical power from the battery. The microcomputer 23 monitors the detection signal of the acceleration sensor 22nd at a predetermined sampling interval to determine the vehicle speed and the angular position of the acceleration sensor 22nd within the corresponding wheel 5a until 5d capture.

After the vehicle speed reaches a predetermined speed, the microcomputer transmits 23 the frame every time the accelerometer 22nd is at a predetermined angular position. For example, the transmitter begins 2 transmit the frame when the vehicle speed reaches the predetermined speed or when the acceleration sensor 22nd reaches a predetermined angular position after the vehicle speed reaches the predetermined speed. The transmitter then transmits 2 the frame every time the accelerometer 22nd at the angular position is the same as the angular position when the frame is first transmitted.

The gravitational acceleration component of the detection signal received from the acceleration sensor 22nd output has a sine curve, as in 3 is shown. The angular position of the accelerometer 22nd is realized based on the sine curve. Accordingly, the frame is transmitted every time the accelerometer is used 22nd reaches the same angular position based on the sine curve.

The TPMS-ECU 3 acquires the gear information indicating the tooth position of each gear 12a until 12d at a predetermined interval, such as every 10 milliseconds, from the brake ECU 10 . The TPMS-ECU 3 measures the time of receipt or the specified time of receipt of the frame sent by each transmitter 2 is transmitted and records the number of edges or the number of teeth of the gears 12a until 12d at the reception timing of the frame among the edge numbers or the tooth numbers obtained.

In this case, it is not always true that the default reception time or the reception timing of the frame sent by the transmitter in question 2 and the timing of the gear information from the brake ECU 10 coincide with each other. For example, the number of edges or the number of teeth of the gear information that are obtained at a time setting that is closest to the reception time of the frame, i.e. the number of edges or the number of teeth of the gear information that is obtained at a time setting immediately before or immediately after the reception time setting of the frame can be obtained using as the number of edges or the number of teeth at the reception timing of the frame.

As another example, the edge number or the number of teeth at the reception timing of the frame may be calculated using the edge number or the number of teeth indicated by the gear information obtained at the timing immediately before or immediately after the reception timing of the frame. For example, an intermediate number between the edge number or the number of teeth of the gear information obtained at the timing immediately before the reception timing of the frame and the edge number of the number of teeth of the gear information obtained at the timing immediately after the reception timing of the frame can be used as the edge number or the number of teeth the reception time of the frame.

The TPMS-ECU 3 detects the number of edges or the number of teeth at the reception timing of the frame every time the TPMS-ECU 3 receives the frame. The TPMS-ECU 3 performs the wheel position detection based on the detected number of edges or teeth at the reception timing of the frame. Specifically, the wheel position detection is performed by determining whether a variation of the detected number of edges or number of teeth at the reception timing of the frame is within a predetermined range which is set based on the number of edges or the number of teeth at the previous reception timing.

Regarding the wheel 5a until 5d on which the relevant transmitter 2 , which transmits the frame, is integrated, transmits the transmitter 2 the frame every time the accelerometer 22nd is at a predetermined angular position. Accordingly, the tooth position indicated by the number of edges or the number of teeth at the reception timing of the frame is substantially the same as the tooth position at the previous reception timing. Accordingly, the variation in the number of edges or the number of teeth in the reception timings of the frame is small and is within a predetermined range. Even if the frames are received many times, the tooth positions indicated by the edge numbers or the tooth numbers at the reception timings of the frame are substantially the same. The variation in the number of edges or the number of teeth at each reception timing of the frame is within a predetermined range which is set based on the number of edges or the number of teeth at the first reception specification of the frame.

On the other hand, it is with regard to the wheel 5a until 5d which are different from the wheel in question 5a until 5d is the tooth position indicated by the number of edges or the number of teeth at the reception timing of the frame sent from the transmitter 2 which is transmitted to the wheel 5a until 5d is integrated, different from the tooth position at the reception timing of the frame, which is received from the transmitter 2 which is transmitted to the wheel in question 5a until 5d is integrated.

The gear 12a until 12d of the wheel speed sensor 11a until 11d namely rotates in connection with the corresponding wheel 5a until 5d . So it is with regard to the wheel object 5a until 5d the tooth position indicated by the number of edges or the number of teeth at the reception timing of the frame is substantially the same. Indeed the wheels did 5a until 5d different turning states due to a road condition, a turn, a lane change and the like. Accordingly, the states of rotation of the wheels are 5a until 5d not completely the same. As such, the tooth position, which is indicated by the number of edges or the number of teeth at the reception timing, is different between the wheels 5a until 5d .

For example, the number of edges is each of gears 12a until 12d zero when the Ignition Switch (IG) is turned on, as in 4th is shown. After the vehicle starts moving, the transmitters transmit 2 the frames. In this case, at the time of receipt of the frame, which from the transmitter 2 which is transmitted to the wheel 5a is integrated, the tooth positions of the gears 12b until 12d which is in connection with the wheels 5b until 5d rotate differently from the tooth position of the gear 12a , which is in connection with the wheel 5a rotates as in the first through third timings in 4th is shown. Accordingly, the wheel position is specified by determining whether there is a variation in the tooth position of the gear 12a until 12d is within a predetermined range.

For example, as in 5A what is shown is the angular position of the transmitter in question 2 if the transmitter in question 2 transmits the frame for the first time, at a first receiving angle An 1 . In this, a deviation permissible range VAR, which is a permissible range of the deviation in the number of edges or the number of teeth, is at a range of 180 degrees centered on the first reception angle AN 1 is set, that is, as a range of +/- 90 degrees of the first reception angle An 1 . For example, the deviation allowance range set based on the number of edges or the number of teeth in the first reception timing is referred to as a first deviation allowance range.

In the case of the number of edges, the first deviation permissible range VAR is selected in the case of a range of +/- 24 of the number of edges at the first preset reception time. In the case of the number of teeth, the first deviation permissible range is VAR with a range of +/- 12th the number of teeth is set at the first reception time specification.

Then, as in 5B is shown, determines whether the number of edges or the number of teeth at the second reception timing of the frame is within the first deviation allowance range VAR which is set by the number of edges or the number of teeth at the first reception timing of the frame. When the frame is received for the second time, there is if the number of edges or the number of teeth of the gearwheel 12a until 12d within the Deviation permissible range VAR is a possibility that the wheel 5a until 5d which this gear 12a until 12d corresponds to the wheel 5a until 5d is on which the relevant transmitter 2 , which transmits the frame, is integrated. Accordingly, this determination result is displayed as "TRUE".

Furthermore, a second deviation allowance range is based on the angular position of the transmitter 2 set when the transmitter 2 transmits the frame the second time. The angular position of the transmitter 2 when the transmitter 2 transmits the frame the second time is referred to as a second reception angle An 2 . As in 5B As shown, the second deviation allowance range is centered on a range of 180 degrees on the second reception angle An 2 set. That is to say, the second deviation admissibility range VAR is within a range of +/- 90 degrees of the second reception angle An 2 set.

Furthermore, a new deviation allowance range VAR is set by an overlapping area when the first deviation allowance range and the second deviation allowance range overlap with each other as a third deviation allowance range. For example, the third deviation allowance range is set to a range in which the number of edges is from 12th until 48 is like in 5B is shown. In this way, the deviation allowance range VAR is reduced to the third deviation allowance range.

As in 5C is shown, it is determined whether the number of edges or the number of teeth at the third reception timing of the frame is within the third deviation allowance range. When the number of edges or the number of teeth of the gear 12a until 12d is not within the third deviation allowance range at the third detection timing of the frame, the wheel is 5a until 5d which this gear 12a until 12d corresponds, not the wheel 5a until 5d on which the relevant transmitter 2 , which transmits the frame, is integrated. Accordingly, the determination result is displayed as "FALSE".

In this case, if the number of edges or the number of teeth is outside the third deviation allowance range at the third reception timing of the frame, the detection result is displayed as “FALSE” even within the first deviation allowance range. In 5C denotes An 3 a third receiving angle of the transmitter 2 when the transmitter 2 transmits the frame the third time.

In this way the microcomputer determines 33 on which bike 5a until 5d the transmitter in question 2 , which transmits the frame, is integrated.

As in 6A is detected every time the frame containing the first identification information ID 1 as the identification information is received, the microcomputer 33 the number of edges or the number of teeth of the gears 12a until 12d . The microcomputer 33 stores the number of edges or the number of teeth for corresponding wheels 5a until 5d such as a front left wheel FL, a front right wheel FR, a rear left wheel RL, and a rear right wheel RR.

Furthermore, every time the frame is received, the microcomputer determines 33 whether each of the detected number of edges or the number of teeth is within the deviation allowance range. If the number of edges is not within the deviation allowable range, the microcomputer closes 33 the corresponding wheel 5a until 5d of candidate bikes 5a until 5d off until a wheel 5a until 5d remains.

The microcomputer 33 registers the wheel 5a until 5d which last remains as the wheel 5a until 5d on which the relevant transmitter 2 that transmits the frame is attached. With regard to the frame which the identification information ID 1 as in 6A is shown, the front right wheel FR and the rear right wheel RR are excluded first, and then the rear left wheel RL is excluded. The front left wheel FL, which is the last remaining, is registered as the wheel on which the relevant transmitter is located 2 is attached.

The microcomputer 33 performs the similar determination for the frames containing the identification information ID 2 , ID 3 , ID 4th exhibit like the 6B until 6D is shown by. In this way, the wheel on which the transmitter in question 2 that transmits the frame is specified or determined. As such, all of the wheels that are the transmitters 2 have to be specified.

When the microcomputer 33 specifies on which bike 5a until 5d any transmitter 2 is attached, the microcomputer stores 33 the relationship between the identification information ID of each transmitter 2 and the position of the corresponding wheel 5a until 5d on which the transmitter 2 is attached.

It is ideal to have all the wheel positions at which the transmitters 2 are attached, to be determined in the manner described above. However, if the transmission angle position of the Transmitters 2 when the transmitter 2 transmits the frame coincides with a position in which the frame is unlikely to reach the TPMS-ECU 3 reached, there is a likelihood that the TPMS-ECU 3 cannot receive the frame every time. In the present embodiment, therefore, the transmission angle position of the transmitter becomes 2 changed every time the transmitter 2 transmits the frame.

The change in the transmission angle position is made by the transmitter 2 carried out. 7A Fig. 11 illustrates an example of transmission angular positions of the transmitter 2 in the corresponding wheel 5a until 5d and 7B illustrates a relationship between the number of times the frame is sent by the transmitter 2 is transmitted, and the transmission angle position of the transmitter 2 .

When the vehicle speed reaches the predetermined speed, such as 5 km / h, the transmitter starts 2 transmit the frame. For example, if the transmitter 2 is at the 0 degree position as a first transmission angular position, such as just above the wheel center axis, the frame is transmitted. After this 10 Seconds pass, the transmitter transmits 2 the frame if the transmitter 2 is at an angular position which is 90 degrees from the first transmission angular position in a direction of rotation of the wheel 5a until 5d is shifted, such as at the same level as the wheel center axis, on a front side of the wheel.

After another 10 seconds have elapsed, the transmitter transmits 2 the frame if the transmitter 2 is at an angular position which is shifted 180 degrees from the first transmission angular position, such as just below the wheel center axis. After another 10 seconds have elapsed, the transmitter transmits 2 the frame when the transmitter is at a transmission angular position which is shifted 270 degrees from the first transmission angular position, such as at the same level as the wheel center axis, on a rear side of the wheel.

In this way, the transmission angle position of the acceleration sensor 22nd changed every time the transmitter 2 transmits the frame. Accordingly, the frames are processed by the TPMS-ECU 3 received correctly.

When the wheel position detection is performed in the manner described above, the TPMS-ECU must 3 Confirm the transmission angle position at which the frame will be transmitted. In the TPMS-ECU 3 the wheel position detection is performed by determining whether the number of edges or the number of teeth at the reception timing of the frame is within the deviation allowance range with respect to the case where the frames are transmitted at the fixed transmission angular position. Accordingly, it is in the case where the transmission angle position of the transmitter 2 is changed every time the frame is transmitted, it is necessary to correct the number of edges or the number of teeth associated with the frame, which is transmitted at a changed transmission angle position, to the number of edges or the number of teeth associated with the frame, which is transmitted at a fixed transmission angle position.

In this case, the frame may have a transmission count representing the number of times the frame has been transmitted. Instead of including the transmission count in the frame, the TPMS-ECU may 3 be configured to realize the transmission angle.

For example, as shown in 8A As shown, the frame includes the transmission count in addition to the identification information ID, the pressure information and the temperature information. In this case, if the TPMS-ECU 3 receives the transmission count, the TPMS-ECU 3 Confirm the transmission angle position when the frame in question is transmitted. That is, the transmission angular position is shifted by a predetermined angle every time the frame is transmitted. Accordingly, the number of times represented by the transfer count corresponds to the angular amount shifted from the first transfer angular position.

As such, based on the transmission count, the edge number or the number of teeth at the reception timing is adjusted by the amount corresponding to the angular amount shifted from the first transmission angular position. Accordingly, the number of edges or the number of teeth at the reception timing of the frame where the transmission angle position is not changed is calculated.

For example, if the number of teeth of the gear 12a until 12d same 48 and the transmission angle position is shifted by 90 degrees every time frame transmission, the number of edges by 24 (96 × 90/360 = 24) corrected. In other words, the number of teeth is increased 12th (48 × 90/360 = 12) corrected. It is then determined whether the corrected number of edges or the number of teeth is within the deviation allowable range.

9 Fig. 13 is a diagram showing an evaluation result of the wheel position of one case Figure 3 illustrates in which the transmission angular position is changed every time the frame is transmitted. As in 9 as shown, the number of edges at the reception timing of each frame is referred to as the number of edges before correction. The corrected number of edges is obtained by correcting the number of edges before the correction by the amount corresponding to the shifted angle. The corrected number of edges corresponds to the number of edges assigned to the frame that is transmitted at the fixed or fixed transmission angle position. Then, the wheel position detection is performed based on the corrected edge numbers.

In 9 Nothing is illustrated as to a case where the frame is not received because the transmitter 2 is at the position of zero. Even if the transfer count is missed at the position of zero, the number of edges or the number of teeth is corrected based on the transfer count. As a result, even if the frame is not received, due to the fact that the transmitter 2 is at the position of zero, corrects the number of edges or the number of teeth correctly.

In a case where the frame does not have the transmission count, the frame will not be received, similar to the transmission at the position of zero. In such a case, when the TPMS-ECU 3 the vehicle speed from the brake ECU 10 receives, the TPMS-ECU 3 determine whether the frame was not transmitted due to the vehicle being stopped or whether the frame reception failed. Accordingly, even if the vehicle is stopped during the wheel position detection, the wheel position detection is less likely to be erroneously performed.

9 only illustrates the evaluation result of the identification information ID 1 . Furthermore, the evaluation results of the identification information ID 2 to ID 4th can be obtained in the similar manner.

8B Fig. 10 illustrates an example of a frame including the identification information ID, the pressure information and the temperature information but not the transmission count. In this case, the TPMS-ECU saves 3 the transmission angle generated by the transmitter 2 is to be postponed. The TPMS-ECU also measures 3 a time which has elapsed from the time frame transmission started. The TPMS-ECU 3 estimates that the transmission angle position is shifted by the amount of the transmission angle corresponding to the time that has passed.

In this case, even if the TPMS-ECU 3 fails to receive the frame due to noise or interference because the TPMS-ECU 3 can estimate the shifted transmission angle, the TPMS-ECU 3 Correct the number of edges or the number of teeth at the time of reception of the frame by the amount that corresponds to the shifted transmission angle. Then the TPMS-ECU determines 3 whether the corrected number of edges or number of teeth is within the deviation allowance range to determine the wheel position.

Even in a case where the transmission count is not used, there is a possibility that the frame at the position of zero is not received. Also in such a case, since the interval of frame transmission is set at a predetermined interval, the shifted transmission angle can be obtained based on the time which has elapsed from the timing of the frame. Accordingly, similarly to the case where the transmission count is used, even if the frame at the position of zero is not received, the edge number or the tooth number is corrected correctly.

Every time the transmitter 2 the frame transmission begins or after the vehicle is detected 1 begins to move, the first frame can be transmitted at the same transmission angle position as, for example, the 0 degree position exactly above the wheel center axis. Alternatively, the transmission angle position if the transmitter 2 the first frame transmits to be changed a predetermined angle every time the transmitter is transmitted 2 the frame transmission begins. For example, the transmission angle position of the transmitter 2 when the transmitter 2 starts transmitting the first frame, changing 90 degrees each time the transmitter is 2 the frame transmission begins.

The TPMS-ECU 3 stores the gear information at the reception timing of the transmitted frame when the vehicle speed reaches the predetermined speed. The TPMS-ECU also deletes or cancels 3 the gear information stored when the vehicle speed is equal to or less than a predetermined vehicle stop determination speed, such as equal to or less than 5 km / h. When the vehicle starts moving again, the TPMS-ECU performs 3 again through the wheel position detection in the manner described above.

After the wheel position detection is performed in the manner described above, the tire pressure detection is performed carried out. When the tire pressure measurement is performed, the frame is sent from each of the transmitters 2 transmitted at a predetermined interval or a predetermined time. The TPMS-ECU 3 receives the frames from all the transmitters 2 every time the transmitter 2 transmits the frame.

The TPMS-ECU 3 determines from which transmitter 2 each of the frames is transmitted based on the ID information stored in the frame, and detects the tire pressure from the information relating to the tire pressure stored in the frame. Accordingly, the TPMS-ECU determines 3 whether the tire pressure of one of the wheels 5a until 5d is decreased, and determines the wheel 5a until 5d which has the tire which is depressurized. When the TPMS-ECU 3 the decrease in the tire pressure of one of the wheels 5a until 5d notifies the TPMS-ECU 3 the measuring device 4th about the acquisition result. Accordingly, the measuring device shows 4th the decrease in tire pressure with the display of the wheel in question 5a until 5d to notify the driver.

As described above, the gear information showing the tooth position of each gear becomes 12a until 12d show which one with the corresponding wheel 5a until 5d is rotated based on the detection signal from the wheel speed sensors 11a until 11d generated. The TPMS-ECU 3 acquires the gear information. The transmitter 2 carries out the frame transmission. The transmission angle position of the transmitter 2 is changed by a predetermined angle every time the transmitter 2 transmits the frame. This increases the chance of the frames in the TPMS-ECU 3 to be received, even if the frame transmission is affected by interference or the like. Compared with the case where the TPMS-ECU 3 repeatedly fails to receive the frames, the wheel position continues to be determined correctly and in a shorter time.

The deviation allowance range is set based on the tooth position at the reception timing of the frame. If the tooth position is not within the set deviation permissible range when the frame is subsequently received, the corresponding gear will 5a until 5d from the candidates of the wheels to which the relevant transmitter 2 , which transmits the frame, is excluded. The wheel 5a until 5d which remains last is registered as the wheel on which the relevant transmitter is 2 is attached. Accordingly, the wheel position is determined with a small amount of data.

Furthermore, the deviation allowance range is renewed to an area in which the first deviation allowance range, which was set based on the tooth position at the first reception timing of the frame, and the second deviation allowance range, which was set based on the tooth position at the subsequent reception timing of the frame, overlap with each other . In this way, the deviation allowance range is reduced. Accordingly, the wheel position is correctly determined in a shorter time.

The transmitter changes taking into account the zero or zero position 2 the transmission angle position to transmit the frame each time the transmitter 2 transmits the frame. The TPMS-ECU 3 corrects the number of edges or the number of teeth at the reception timing of the frame to the number of edges or the number of teeth assigned to the frame that is transmitted at the fixed transmission angle position. In this case, even if any transmission angle position is at the position of zero, as the transmitter 2 transmits the frame at different transmission angle positions, the frame can be transmitted from the position other than the position of zero. Accordingly, the wheel position can be correctly determined.

The frame transmission is started when the vehicle speed is equal to or greater than the predetermined speed. Likewise is the position of the transmitter 2 within the corresponding wheel 5a until 5d using the accelerometer 22nd recorded. Accordingly, although the wheel position detection is performed only after the vehicle starts moving, the wheel position detection can be started immediately after the vehicle starts moving. The wheel position detection can be performed based on an intensity of a signal output from a trigger device. In the present embodiment, on the other hand, the wheel position detection can be performed without using the trigger device.

(Other embodiments)

In the embodiment described above, the transmitter transmits 2 the frame at the different transmission angle positions and the TPMS-ECU 3 corrects the number of edges or the number of teeth assigned to the frame transmitted at the different transmission angle position to the number of edges or the number of teeth assigned to the frame transmitted at the fixed transmission angle position. It is however, it is not always necessary to correct the number of edges or the number of teeth.

Alternatively, the determination of the wheel position, i.e. the determination of whether the number of edges or the number of teeth is within the deviation allowance range, can be performed using only the number of edges or the number of teeth at the reception timings of the frames transmitted at the same transmission angle position. For example, the wheel position detection can be carried out only based on the edge numbers or the tooth numbers in the reception timings of the frames which are transmitted when the transmission angle position is at the 0 degree position. As another example, the wheel position detection can be performed based only on the edge numbers or the tooth numbers of the reception timings of the frames transmitted when the transmission angular position is at a 90 degree position.

In the embodiment described above, as the example, the transmission angular position is shifted by 90 degrees every time the transmitter 2 transmits the frame, such as a 0 degree position, 90 degree position, 180 degree position, and 270 degree position in the direction of rotation of the wheel 5a until 5d . However, the transmission angular position can be any angle other than 90 degrees in the direction of rotation of the wheel 5a until 5d be moved. Likewise, it is not always necessary to shift the transmission angle position by a fixed angle. For example, the transmission angle position can be shifted by a different angle in the direction of rotation of the wheel as long as the TPMS-ECU 3 can realize the amount that the transmission angle position is shifted. That is, the predetermined shifted angle is not limited to the fixed angle but may be a variable angle.

In the embodiment described above, the position in which the transmitter is 2 exactly above the wheel center axis is defined as the zero position as the reference position. However, the zero position can be at any position in a circumferential direction of the wheel 5a until 5d can be set.

In the embodiment described above, the TPMS-ECU corrects 3 the tooth position, which is represented by the number of edges or the number of teeth. Instead of correcting the tooth position in the TPMS-ECU 3 the deviation allowance range can be changed according to the transmission angle position. For example, a second deviation allowance range, which is used for determining the number of edges or the number of teeth in the second reception time specification of the frame, can be set to a range which is provided by adding a range of 90 degrees to a range of 90 degrees in the center of the first receiving angle An 1 . Furthermore, a third deviation allowance range, which is used for determining the number of edges or the number of teeth at the third reception timing of the frame, can be set to a range which is obtained by adding a range of 90 degrees to an overlapping deviation allowance range between the second deviation allowance range and an area of 90 degrees centered on the second receiving angle An 2 is provided. The fourth deviation allowance range can be set in a similar manner.

Namely, the deviation allowance range can be changed every time the frame is received and can be set based on the gear position when the frame is received. Furthermore, an overlapping area between the deviation allowance range which is set when the frame is received and an area to which 90 degrees are added to the deviation allowance range which is set when the previous frame is received can be calculated. Further, the deviation allowance range can be set to a range in which the foregoing overlapping deviation allowance range and an area to which 90 degrees are added to the foregoing overlapping deviation allowance range overlap each other. The number of times of adding 90 degrees to the deviation allowance range corresponds to the number of times of shifting the transmission angular position. Accordingly, the number of times of adding or adding 90 degrees can be set based on the elapsed time from the start of the frame transmission or the transmission count. Even in such a case, advantageous effects similar to the case where the number of edges or the number of teeth are corrected will be obtained.

In the embodiment described above, the transfer count is used. As another example, the number of edges or the number of teeth to be corrected may be used in place of the transfer count.

In the embodiment described above, the deviation allowance range in the reception timing of each frame becomes in such a manner changed so that the deviation allowance range is gradually or gradually reduced. On the other hand, each deviation allowance range set centrally at the tooth position is constant. The deviation permissible range, which is set centered on the tooth position, can, however, be changeable.

For example, the variation in tooth positions is likely to increase as the vehicle speed increases. Accordingly, each deviation allowance range set centrally at the tooth position can be increased with the increase in the vehicle speed. In such a case, the deviation allowance range can still be set correctly.

It is likely that the detection accuracy at a given time if the angle of the transmitter 2 is at the predetermined angular position, with an increase in the interval of sampling the accelerations in the acceleration detection by the acceleration sensor 22nd decreased. Accordingly, the deviation allowance range can be changed according to the decrease in the detection accuracy. Even in such a case, the deviation allowance range continues to be set correctly. In this case the transmitter implements 2 an interval of sampling of accelerations. Accordingly, the transmitter can 2 Include or have data for determining the deviation allowance range in the frame.

In the embodiment described above, the TPMS-ECU acquires 3 the gear information from the brake ECU 10 . As another example, the TPMS-ECU 3 acquire the edge number or the tooth number as the gear information from another ECU. As another example, the TPMS-ECU 30th the detection signals from the wheel speed sensors 11a until 11d received and the number of edges or the number of teeth of each gear 12a until 12d obtained based on the obtained detection signal.

In the embodiment described above, the TPMS-ECU are 3 and the brake ECU 10 separated. As another example, the TPMS-ECU 3 and the brake ECU 10 be integrated into a single ECU. That is, the TPMS-ECU 3 and the brake ECU 10 can be provided by a single ECU. In such a case, the ECU can directly use the detection signals from the wheel speed sensors 11a until 11d received and the number of edges or the number of teeth of each gear 12a until 12d based on the received detection signal.

In this case, the ECU can continuously obtain the edge numbers or the teeth numbers. Accordingly, the wheel position detection based on the gear information is performed at an exact reception timing of the frame different from the case where the gear information is received at the predetermined interval.

In the embodiment described above, the position detecting device is exemplified on the vehicle 1 which four wheels 5a until 5d has started. The wheel position detecting device can be applied to a vehicle having wheels other than four.

In the embodiment described above, the deviation allowance range is set based on the tooth position of the gear information, and the wheel position is specified by determining whether the tooth position is within the deviation allowance range. Furthermore, the deviation allowance range is decreased by setting the overlapping area, wherein the preceding deviation allowance range and the subsequent deviation allowance range overlap with each other as the new deviation allowance range. In this case, the wheel position is determined or specified in the shorter time.

However, even if the deviation allowance range is not decreased, the frame can be correctly passed through the TPMS-ECU 3 by shifting the transmission angle position of the transmitter 2 at the predetermined angle every time the transmitter 2 transmits the frame. Also in this case, compared with the case where the frame cannot be continuously received, the wheel position can still be correctly determined in the short time. Furthermore, the wheel position is determined by using the deviation allowance range of the tooth position. As another example, the wheel position may be determined based on a standard deviation of the tooth positions at the multiple frame transmission timings. In this case, too, the similar advantageous effects are achieved by shifting the transmission angle position of the transmitter 2 every time the frame is transmitted.

In the present disclosure, the wheel speed sensors detect 11a until 11d at least the penetration or the passage of the teeth of the gears 12a until 12d which one with the wheels 5a until 5d to be turned around. The gears 12a until 12d may have a structure in which teeth have conductive outer surfaces and intermediate portions between the teeth have magnetic reluctance different from the outer surfaces of the teeth. The gears 12a until 12d namely can have any structure. For example, the gears 12a until 12d be a general gear which has protrusions and recesses on an outer surface of the gear. The protrusions have conductivity and the recesses are spaces that provide non-conductive sections. As another example, the gears can 12a until 12d be a rotary switch, the outer surface of which has conductive portions and non-conductive insulating portions, as in FIG JP H1048233 A is described.

While only the selected exemplary embodiments have been chosen to illustrate the present disclosure, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made therein without departing from the scope and disclosure as defined in the appended claims is to deviate. Furthermore, the foregoing description of the exemplary embodiments in accordance with the present disclosure is provided for illustration only and not for the purpose of limiting the disclosure as defined by the appended claims and their equivalents.

Claims (7)

A wheel position detecting device for a vehicle having a vehicle body (6) and a plurality of wheels (5a to 5d), the wheel position detecting device comprising: a transmitter (2) connected to each of the plurality of wheels (5a to 5d) ) is integrated, the transmitter (2) having a first control unit (23), the first control unit (23) having a frame which has identification information which is specific for the transmitter (2); and a receiver (3) which is integrated on the vehicle body (6), wherein the receiver (3) has an antenna (31) and a second control unit (33), the second control unit (33) the frame, which of the Transmitter (2) is transmitted via the antenna (31), wherein the second control unit (33) performs a wheel position detection to determine on which of the plurality of wheels (5a to 5d) the transmitter (2), which the frame transmits, is integrated, and to store a relationship between the identification information of the transmitter (2) and a corresponding wheel (5a to 5d) on which the transmitter (2) is integrated, the transmitter (2) having an acceleration sensor (22 ) which outputs a detection signal according to an acceleration which has a gravitational acceleration component which varies with the rotation of the corresponding wheel (5a to 5d) on which the transmitter (2) is integrated, d The first control unit (23) detects an angular position of the transmitter (2) relative to a reference position based on the gravitational acceleration component, which is provided by the detection signal of the acceleration sensor (22), the reference position to any position in a circumferential direction of the corresponding wheel ( 5a to 5d), wherein the first control unit (23) transmits the frame when the transmitter (2) is at a transmission angle position, and wherein the first control unit (23) changes the transmission angle position by a predetermined angle every time the frame is transmitted , the wheel position detecting device further comprising: a wheel speed sensor (11a to 11d) which is arranged to correspond to each of the wheels (5a to 5d) to be a tooth of a gear (12a to 12d) which is located in Connection with the corresponding wheel (5a to 5d) rotates, grasping the tooth rad (12a to 12d) has conductive portions as teeth and intermediate portions between the conductive portions, the intermediate portions having a magnetic resistance different from the conductive portions, the second control unit (33) acquiring gear information indicating a tooth position of the gear (12a to 12d) based on a detection signal of the wheel speed sensor (11a to 11d), and the second control unit (33) determines on which of the plurality of wheels (5a to 5d) the transmitter is integrated, based on the tooth position of the gear at a reception timing of the Frames, wherein the second control unit (33) sets a deviation permissible range of the tooth position based on the tooth position of the gear (12a to 12d) at the reception timing of the frame, the second control unit (33) determines whether the tooth position of the gear (12a to 12d) is too a subsequent reception time specification of the frame in If the tooth position of the gearwheel (12a to 12d) is not within the deviation allowance range at the subsequent reception time, the second control unit (33) is the gear (5a to 5d), which corresponds to the gearwheel (12a to 12d), of Excludes candidate wheels (5a to 5d) until one wheel (5a to 5d) remains and one wheel (5a to 5d) registered as the wheel (5a to 5d) on which the transmitter (2) is integrated, the second control unit (33) changes the deviation allowance range every time the frame is received, the second control unit (33) an overlapping range between the deviation allowance range and a previous deviation allowance range, which was set based on the tooth position of the gear (12a to 12d) at a previous reception timing of the frame, as a new deviation allowance range, the second control unit (33) sets the tooth position of the gear (12a to 12d), which to the Receiving time preset is detected, which is assigned to the frame which is transmitted at a transmission angle position which is changed by the first control unit (23), corrected to a tooth position which is assigned to a frame which is transmitted to a fixed transmission angle position, and the second tax unit (33) determines whether the tooth position of the gear (12a to 12d) that is corrected is within the deviation allowance range in order to determine the gear (5a to 5d) on which the transmitter (2) is integrated. A wheel position detecting device for a vehicle having a vehicle body (6) and a plurality of wheels (5a to 5d), the The wheel position detection device comprises: a transmitter (2) which is integrated on each of the plurality of wheels (5a to 5d), the transmitter (2) having a first control unit (23), the first control unit (23) having a frame which has identification information specific to the transmitter (2); and a receiver (3) which is integrated on the vehicle body (6), wherein the receiver (3) has an antenna (31) and a second control unit (33), the second control unit (33) the frame, which of the Transmitter (2) is transmitted via the antenna (31), wherein the second control unit (33) performs a wheel position detection to determine on which of the plurality of wheels (5a to 5d) the transmitter (2), which the frame transmits, is integrated, and to store a relationship between the identification information of the transmitter (2) and a corresponding wheel (5a to 5d) on which the transmitter (2) is integrated, the transmitter (2) having an acceleration sensor (22 ) which outputs a detection signal according to an acceleration which has a gravitational acceleration component which varies with the rotation of the corresponding wheel (5a to 5d) on which the transmitter (2) is integrated, d The first control unit (23) detects an angular position of the transmitter (2) relative to a reference position based on the gravitational acceleration component, which is provided by the detection signal of the acceleration sensor (22), the reference position to any position in a circumferential direction of the corresponding wheel ( 5a to 5d), wherein the first control unit (23) transmits the frame when the transmitter (2) is at a transmission angle position, and wherein the first control unit (23) changes the transmission angle position by a predetermined angle every time the frame is transmitted , the wheel position detecting device further comprising: a wheel speed sensor (11a to 11d) which is arranged to correspond to each of the wheels (5a to 5d) to be a tooth of a gear (12a to 12d) which is located in Connection with the corresponding wheel (5a to 5d) rotates, grasping the tooth rad (12a to 12d) has conductive portions as teeth and intermediate portions between the conductive portions, the intermediate portions having a magnetic resistance different from the conductive portions, the second control unit (33) acquiring gear information indicating a tooth position of the gear (12a to 12d) based on a detection signal of the wheel speed sensor (11a to 11d), and the second control unit (33) determines on which of the plurality of wheels (5a to 5d) the transmitter is integrated, based on the tooth position of the gear at a reception timing of the Frames, wherein the second control unit (33) stores the predetermined angle which is changed by the first control unit (23), the second control unit (33) a time which has elapsed since the transmitter (2) starts to transmit the frame , as an elapsed time, the second control unit (33) measures the transmission angle pos ition of the transmitter (2) at the reception timing of the frame based on the elapsed time, and the second control unit (33) estimates the tooth position of the gearwheel (12a to 12d), which is detected at the reception timing, which is assigned to the frame, which at a transmission angle position which is changed by the first control unit (23) changes to a tooth position which is assigned to a frame which is transmitted to a fixed transmission angle position. A wheel position detecting device for a vehicle having a vehicle body (6) and a plurality of wheels (5a to 5d), the wheel position detecting device comprising: a transmitter (2) connected to each of the plurality of wheels (5a to 5d) ) is integrated, the transmitter (2) having a first control unit (23), the first control unit (23) having a frame which has identification information which is specific for the transmitter (2); and a receiver (3) which is integrated on the vehicle body (6), wherein the receiver (3) has an antenna (31) and a second control unit (33), the second control unit (33) the frame, which of the Transmitter (2) is transmitted via the antenna (31), wherein the second control unit (33) performs a wheel position detection to determine on which of the plurality of wheels (5a to 5d) the transmitter (2), which the frame transmits, is integrated, and to store a relationship between the identification information of the transmitter (2) and a corresponding wheel (5a to 5d) on which the transmitter (2) is integrated, the transmitter (2) having an acceleration sensor (22 ) which outputs a detection signal according to an acceleration which has a gravitational acceleration component which varies with the rotation of the corresponding wheel (5a to 5d) on which the transmitter (2) is integrated, d The first control unit (23) detects an angular position of the transmitter (2) relative to a reference position based on the gravitational acceleration component, which is provided by the detection signal of the acceleration sensor (22), the reference position to any position in a circumferential direction of the corresponding wheel ( 5a to 5d) is set, wherein the first control unit (23) transmits the frame when the transmitter (2) is at a transmission angle position, and wherein the first control unit (23) changes the transmission angle position by a predetermined angle every time the frame is transmitted, the wheel position detecting device further comprising: a wheel speed sensor (11a to 11d) which is arranged so that it corresponds to each of the wheels (5a to 5d) to a tooth of a gear (12a to 12d) which is in connection with the corresponding wheel (5a to 5d), the gear (12a to 12d) having conductive portions as teeth and intermediate portions between the conductive portions, the intermediate portions having a magnetic resistance different from the conductive portions, the second control unit (33) having gear information obtains a tooth position of the gear (12a to 12d) based on a detection signal of the wheel speed sensor (11a to 11d), and the second control unit (33) determines on which of the plurality of wheels (5a to 5d) the transmitter is integrated, based on the tooth position of the gear at a reception timing of the frame, the first The control unit (23) generates the frame, which generates a transmission count representing a number of times the frame transmission, and the second control unit (33) generates the tooth position of the gear (12a to 12d) which is detected at the reception timing which the frame which is transmitted at a transmission angle position which is changed by the first control unit (23) changes to a tooth position which is associated with a frame which is transmitted to a fixed transmission angle position, based on the transmission count. A wheel position detecting device for a vehicle having a vehicle body (6) and a plurality of wheels (5a to 5d), the wheel position detecting device comprising: a transmitter (2) which is integrated on each of the plurality of wheels (5a to 5d), the transmitter (2) having a first control unit (23), the first control unit (23) having a frame which contains identification information which is specific to the transmitter (2), generates and transmits; and a receiver (3) which is integrated on the vehicle body (6), the receiver (3) having an antenna (31) and a second control unit (33), the second control unit (33) the frame which is transmitted by the transmitter (2) is transmitted via the antenna (31), the second control unit (33) performing a wheel position detection in order to determine on which of the plurality of wheels (5a to 5d) the transmitter (2) which is transmitting the frame , is integrated, and to store a relationship between the identification information of the transmitter (2) and a corresponding wheel (5a to 5d) on which the transmitter (2) is integrated, wherein the transmitter (2) has an acceleration sensor (22) which outputs a detection signal according to an acceleration which has a gravitational acceleration component which varies with the rotation of the corresponding wheel (5a to 5d) on which the transmitter (2) is integrated , wherein the first control unit (23) detects an angular position of the transmitter (2) relative to a reference position based on the gravitational acceleration component provided by the detection signal of the acceleration sensor (22), the reference position to an arbitrary position in a circumferential direction of the corresponding wheel (5a to 5d) is set, wherein the first control unit (23) transmits the frame when the transmitter (2) is at a transmission angular position, and wherein the first control unit (23) changes the transmission angular position by a predetermined angle each time the frame is transmitted, wherein the wheel position detecting device further comprises: a wheel speed sensor (11a to 11d) which is arranged to correspond to each of the wheels (5a to 5d) to detect a tooth of a gear (12a to 12d) which is associated with the corresponding wheel (5a to 5d) rotates, the gear (12a to 12d) having conductive portions as teeth and intermediate portions between the conductive portions, the intermediate portions having a magnetic resistance different from the conductive portions, wherein the second control unit (33) obtains gear information indicating a tooth position of the gear (12a to 12d) based on a detection signal of the wheel speed sensor (11a to 11d), wherein the second control unit (33) sets a deviation allowance range of the tooth position based on the tooth position of the gear (12a to 12d) at the reception timing of the frame, wherein the second control unit (33) of the receiver (3) determines whether the tooth position of the gearwheel (12a to 12d) is within the deviation permissible range at a subsequent reception time specification of the frame, wherein, if the tooth position of the gear (12a to 12d) is not within the deviation allowance range in the subsequent reception timing, the second control unit (33) excludes the wheel (5a to 5d) corresponding to the gear (12a to 12d) from candidate wheels (5a to 5d) until one wheel (5a to 5d) remains, and the one wheel (5a to 5d) registered as the wheel (5a to 5d) on which the transmitter (2) is integrated, wherein the second control unit (33) changes the deviation allowance range every time the frame is received, wherein the second control unit (33) calculates an overlapping area between the deviation allowance range and a first added deviation allowance range, which is provided by adding a predetermined deviation allowance range to a previous deviation allowance range which is set at a previous reception timing of the frame, and wherein the second control unit (33) sets a second added deviation allowance range, which is provided by adding the predetermined deviation allowance range to the calculated overlapping range, as a new deviation allowance range. Wheel position detection device according to one of the Claims 1 until 4th wherein the second control unit (33) increases the deviation allowance range with an increase in a vehicle speed. Wheel position detection device according to one of the Claims 1 until 5 wherein the first control unit (23) generates the frame having data for determining the deviation allowance range set by the second control unit (33). A tire pressure detecting device comprising: the wheel position detecting device according to any one of Claims 1 until 6th wherein the transmitter (2) has a detection unit (21) which outputs a detection signal according to a tire pressure of the corresponding wheel (5a to 5d), the first control unit (23) having tire pressure information which indicates the detection signal of the detection unit (21), wherein the first control unit (23) includes the tire pressure information in the frame and transmits the frame, and wherein the second control unit (33) detects the tire pressure of each wheel (5a to 5d) based on the tire pressure information contained in the frame .

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